What is the probability that their next child will be a female who has normal vision and is type O?

In humans, the ABO blood type is under the control of autosomal multiple alleles. Red-green color blindness is a recessive x-linked trait. If two parents who are both type A and have normal vision produce a son who is color-blind and type O, what is the probability that their next child will be a female who has normal vision and is type O?

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In humans, the ABO blood type is under the control of autosomal multiple alleles. Red-green color blindness is a recessive x-linked trait. If two parents who are both type A and have normal vision produce a son who is color-blind and type O, what is the probability that their next child will be a female who has normal vision and is type O?

Response: Let's address each trait separately. At the end, we can combine them to finish the solution.

Two parents are both A-type blood but produce a son with O-type blood. How can this be?

Each parent must be heterozygous for A/O. If we use the "^" symbol for superscript and the "I" letter as the letter designating blood type, then each parent must be: I^A/I^O.